Nearly four billion years ago, life arose on Earth. Life appeared because our planet had a rocky surface, liquid water and a blanketing atmosphere. But life thrived thanks to another necessary ingredient: the presence of a protective magnetic field. A new study with the participation of the University of Göttingen shows that a magnetic field plays a key role in making a planet conducive to life. The results were published in The Astrophysical Journal Letters.
The scientists studied Kappa Ceti, a star located 30 light years away in the constellation Cetus, the Whale. Kappa Ceti is remarkably similar to our Sun, but younger. It is magnetically very active and its surface is blotched with many giant starspots, like sunspots, but larger and more numerous.
Computer model of the magnetic field lines of the star Kappa Ceti as gray lines looping out from the star’s surface.
Credit: Do Nascimento et al.
It also propels a steady stream of plasma or ionized gases out into space, a stellar wind that is 50 times stronger than our Sun’s solar wind. Kappa Ceti is between 400 and 600 million years old and its age roughly corresponds to the time when life first appeared on Earth.
“Studying Kappa Ceti can give us insight into the early history of our own solar system,” explains co-author Dr. Sandra Jeffers from Göttingen University’s Institute for Astrophysics.
Without the protection of a magnetic field, such a fierce stellar wind would batter the atmosphere of any planet in the habitable zone – a fate that in our solar system the planet Mars suffered.
In their study, the scientists modeled the strong stellar wind of Kappa Ceti and its effect on a young Earth. “The early Earth’s magnetic field is expected to have been about as strong as it is today, or slightly weaker,” says Dr. Jeffers.
“Depending on the assumed strength, we found that the resulting protected region or magnetosphere of Earth would be about one-third to half as large as it is today. The early Earth didn’t have as much protection as it has now, but it had enough in order to preserve the necessary conditions for life.”
Kappa Ceti also shows evidence of superflares, enormous eruptions that release 10 to 100 million times more energy than the largest flares ever observed on our Sun. Flares that energetic can strip a planet’s atmosphere. By studying Kappa Ceti, the researchers hope to learn how frequently it produces superflares, and therefore how often our Sun might have erupted in its youth.
Original publication: J.-D. Do Nascimento, Jr. et al. Magnetic field and wind of Kappa Ceti: Towards the planetary habitability of the young Sun when life arose on Earth. The Astrophysical Journal Letters 2016. http://arxiv.org/pdf/1603.03937v1.pdf.
Dr. Sandra Jeffers
University of Göttingen
Faculty of Physics – Institute for Astrophysics
Friedrich-Hund-Platz 1, 37077 Göttingen, Germany, Phone +49 551 39-13810
Thomas Richter | idw - Informationsdienst Wissenschaft
Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University
Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences